Well, there's the fact that it's one of the major hubbs of one of the largest crime syndicates in the galaxy. There's also the banthas, which are sorta like cows in our world, used for meat, leather, etc. We know those exist on Tattooine, but I'm not sure if they exist anywhere else.
Unless Bantha meat is some delicacy that is worth its weight in gold, the numbers that such a barren planet can support are tiny and hardly making any farmer rich. The economics of importing bantha meat from Tattooine as opposed to eating the meat of local Nerfs on, say, Alderaan, is just not there.
And generally, the price of food tends to be waay low in any heavily industrialized and mechanized society. Just look at Earth nowadays. The only ones even breaking even are those getting subsidies, even in the most fertile areas. You're not going to make the big bucks raising Banthas in a desert, sorry. Not when you're competing with people producing stuff on fertile and technologically advanced places like Alderaan or Dantooine.
That part makes economic sense, particularly for someone looking to hide, or someone who's never known any other life.
Not in any realistic way. It can be handwaved as making some sense by Lucas, but it's really in the same way as it can be handwaved that a city of 1500 people can make living with wood they're not having much of a market for.
Even if you're looking to hide, there is no point in going to a place where even water costs a mint, being produced in tiny quantities per farmer, and where just a shower or brushing your teeth can set you back accordingly. You'd need to be incredibly rich to even afford to stay hidden there for any extended time, at that point, frankly, why don't you go hide in some better place AND cheaper place like Nar Shaddaa?
Even the excuse of supplying stuff for the smuggler cities, runs into the problem that smuggling in the SW universe is itself something that doesn't make much sense. It's exactly the cliche of big, expensive, top-technology ships carrying tiny amounts of inexpensive goods. Whether it's Han Solo or the smuggler in the SW:TOR intro, or whatever, the ships are invariably touted as the fastest in <insert chunk of space or class>, and shown as beiing able to outmaneuver fighters, and withstand attacks by whole squadrons of fighters and bombers. We're talking things that are pushing the technology envelope, and that ain't cheap. Yet invariably they don't even have space for more than tiny amounts of anything on board, and even if they're carrying drugs ("spice"), it's the stuff that apparently every junkie can afford. But occasionally we hear even of inexpensive stuff like food being smuggled.
So already it's pretty much something that you have to take on faith that it even breaks even. (Then again, Han Solo obviously wasn't breaking even.) Deciding to then spend your time in THE planed with the worst bang-per-buck, the one which has almost no services or more entertainment than a cheap bar, and everything including a glass of water is waaay too expensive... why? What sense does that add to something that's already at best borderline? Why not just skip it entirely and stick to whatever planets A and B you're smuggling stuff between? You must be obviously able to fake your ID or whatever it takes to land on both, or you'll not be able to load from one and unload to the other. So why not just stay in a cheaper cantina on either of them, since you're already there? What sense does it makes to go to a planet that's both crap AND overpriced?
The premise is basically like saying that someone transporting drugs by submarine from Colombia to the USA, would need to spend their time in between runs in some imaginary uber-expensive hotel in Haiti. Why? Why not just stay in Colombia or the USA?
You're making a fundamental assumption, one which is demonstrably not true: namely, that cultures remain the same.
It's actually a thing that's stated, implied, or even explicitly shown in most settings. The Mandalorians in SW, for example, are shown as being and staying insanely war-obsessed for hundreds or thousands of years.
The Ferengi in ST have even their current set of rules of acquisition since the time of the first Grand Nagus of their alliance, and presumably a mercantile system for even longer. One of their criticisms of humanity is that it took humans 6000 years to come up with centralized banking, so presumably they had theirs much earlier. And at any rate, they don't change much in the centuries between they're first introduced in ST:NG to their depiction in STO.
It's not just my assumption that such cultures don't change, it's often really canon that they don't change a dysfunctional unidimensional culture for a lot more time than it would realistically be able to coast on its past capital before crashing horribly.
They don't. Rome, for example, used to be divided into two quite clearly defined classes fo people (been too long since I've looked into it, so I can't remember their names).
Not sure which you mean. Patricians vs plebeians? Actually that was a historical division by lineage, and you could skip between the two by adoption or marriage. Also by the time of the empire, there were plenty of rich plebeians and even more dirt-poor patricians.
But more importantly, both were supposed to show the same chest-thumping martial spirit, but both were actually more complex than that. Most of Rome's power was actually driven by the economy, and we see even hereditary senators later trying to get a slice of the trade pie by making trade companies in the name of their freedmen.
Rome was a very complex thing, with a rich culture, and a mix of economic, artistic, military, etc, aspects, not just one like the "planet of hats" in some SF settings.
Is Italy still so strictly divided?
No, but it also never passed through any historical point where a culture could be defined by just one trait.
Ditto.
Germany used to be a bunch of warring clans only occasionally lead by a single ruler. Is that still the case?
Germany used to be a more complex thing than Klingons at any point in known history, including its stage of hunter-gatherer barbarians. They had a functioning economy to support them, they mined (German iron was very prized by the Romans), they crafted, they traded with the Romans, they made alliances with other nearby confederations (see, for example, Caesar's account of the migration of the Helvetii,) they had their own art, etc. There simply is no point in the past that is even comparable to those one-aspect cultures from a lot of SF, and which would thus justify that kind of one-aspect culture.
It's perfectly plausible for a culture to shift, AFTER it's developed interstellar travel, into a culture that worships warriors. It could be that they were nice enough folks, until they encountered some alien race that tried to enslave THEM. There was a war, and the first aliens enslaved the second as punishment. Then they realized that this made their lives a LOT easier, and a lot of songs and stories got made about the warriors, resulting in a few generations that practically worshiped the military. Once you have a significant number of children being brought up to believe something, it can be said to be part of the culture. Thus, a race no more hostile than your average middle-class American can become the Klingons in a single interstellar war. And if you get a few generals in political office (not uncommon at all--our own government has had numerous military heros in charge of it) the culture could easily be manipulated even further toward worshiping the military. After all, a general is a military rank, and would be set for life if not worshiped as a god.
Handwaving imaginary scenarios is good and fine if you're writing SF, but not if we're discussing the realism of such situations, or if they could actually survive any significant amount of time -- much less the thousands of years they get in some settings -- as such a dysfunctional society.
Middle-class Americans CANNOT become Klingons any more than they can become Vulcans, because humans don't work that way, and they'd still have a pyramid of needs that includes more than war. They could start chest-thumping for war all right, but you'll still have people trying to get their status and recognition by other means, e.g., by getting rich. The same would probably apply to alien species too. A species which wasn't too dysfunctional to reach warp travel stage, won't change their brain wiring over night into everyone being unidimensional.
Plus, again, that's not what most of such settings tell us. The general trope seems to be the contrary, that cultures that evolved on lush planets are all peaceful and wise and were so for as long as anyone remembers, and cultures that evolved on harsh planets, are naturally inclined to solve everything by shooting first and asking later. The time scales at which a dysfunctional society existed tend to be anywhere between thousands of years, if they just moved there from somewhere else, to evolutionary timescales if that's actually their home planet.
Very rarely some series actually does explore the question of "so how did those get to be a space empire if they're THAT dysfunctional?", like for example Enterprise did for the Klingons and Vulcans. But then that tends to result in fanboys bemoaning that even considering an age where the Klingons weren't driven by one-track-mindededness and rabid adherence to warrior codes is contrary to the original spirit and vision.
Dune, for one. He tied his economics pretty tightly to a single comodity, but he discussed the implications of it (in fact, that was the climax of several of the books). Paul Atreides basically threatened to destroy the economy of the empire if they didn't do what he said, which is how he won in the end.
Duly noted, Dune sorta manages to handwave that kind of economy more convincingly than other settings... never mind that that kind of economy or society never actually existed, or that the whole setting needs bending everything else, from physics to basic human reactions, into a pretzel, just to make it work. It's one of those things that seem profound mostly by virtue of actually not making much sense.